Colorectal cancer (CRC) is the third most commonly diagnosed cancer worldwide, with nearly one million new cases and 500,000 deaths each year. This means that CRC is the second-most deadly cancer after lung cancer.

In the US more than 140,000 individuals alone are diagnosed and 55,000 people die of the disease. For Norway the number of people diagnosed with CRC is 3,200, claiming nearly 1,600 lives annually.

Colon polyp. Courtesy of Dr. Endlicher, University of Regensburg.

The clinical symptoms of colorectal cancer may be
- blood in faeces
- abdominal discomfort and pain
- change in bowel habits
- iron-deficiency anemia
- weight loss
- new-onset constipation

Unfortunately the cure-rate is only about 50% because of invasive disease at time of diagnosis in many patients. CRC is a slow-growing disease and curable when diagnosed early. This is the reason why the European and US Medical Community recommend inspection of the colon (colonoscopy) to check for precancerous lesions (polyps) that easily can be be removed by local surgery. Public screening programmes have been introduced in several countries in Europe, but is not available in Norway.

During sigmoidoscopy or colonoscopy the doctor inspects respectively the first part or the whole colon to look for cancer and precancerous  lesions. Superficial lesions are removed by local surgery, if invasive disease systemic chemotherapy is necessary. 

Visit American Cancer Society's website for additional information about gastrointestinal cancers.